1. Field of the Invention
The present invention relates to a system for removing items from a flowing liquid stream. In particular, the invention is directed to an improved dewatering system for use in separating liquid, such as water, from potatoes, other root crops, vegetation, or other solid items entrained in a flowing stream of the liquid.
2. Description of the Related Art
It is known in the art to convey, through a processing facility, solid items in a stream of liquid and then to separate the items from the liquid prior to a downstream processing procedure. For example, potatoes or other root crops may be conveyed through a processing facility entrained in a stream of liquid (e.g., water or brine). At some point, however, e.g, prior to slicing or peeling the potatoes or other root crops, the crops must be separated from the liquid (i.e., dewatered). Traditionally in the potato processing industry, potatoes have been dewatered by passing the stream of water (or other conveying liquid) and the entrained potatoes from a flume carrying the stream over a grid through which the water, but not the potatoes, may pass. Such grids would typically be oriented at a relatively steep decline (e.g. 35-45 degrees) and would traverse a significant drop (e.g., on the order of 36 inches) to ensure that the potatoes would continue forward movement after being dewatered. Moreover, the volume of liquid flow (typically on the order of 500 to 1500 gallons/minute) required that the grid be rather wide (e.g., on the order of 3 feet or more) to accommodate the volume. Also, the significant drop of the grid would create a large amount of hydrodynamic energy, and the falling water would merely impinge on a surface beneath the grid, thus resulting in significant splashing of the water and bruised or otherwise damaged potatoes. Furthermore, to ensure adequate dewatering, in view of the amount of splashing created during the dewatering process, it is necessary for the conventional grids to be quite long (e.g. 36-48 inches). Such large dewatering systems are space-consuming, and the large width of the system often requires a downstream concentrating conveyor to bring the potatoes into a narrower stream for feeding the potatoes to a subsequent processing device, e.g., a slicer or peeler.
Accordingly, there is a need for a dewatering system that effectively removes the solid items from a stream of liquid in a relatively small envelope and in such a manner so as not to subject the items to hard collisions and other abuse.
The present invention overcomes the shortcomings of existing devices and methods of item dewatering.
In accordance with aspects of the present invention the shortcomings of prior art dewatering systems are overcome by a dewatering apparatus for substantially separating liquid from a flowing stream of liquid and solid items entrained therein. The dewatering apparatus comprises a primary grid having openings through which a substantial portion of the flowing liquid stream may pass but through which at least a substantial portion of the solid items entrained in the liquid will not pass. The primary grid separates a substantial portion of the liquid from a substantial portion of the solid items and conveys the separated solid items toward a discharge of the primary grid. The apparatus further comprises a baffle positioned beneath the primary grid to capture and redirect a substantial portion of the liquid stream passing through the openings of the primary grid. The baffle has a leading portion proximate the primary grid. The primary grid and the leading portion are oriented so that a top surface of the stream passes through the primary grid at an orientation that is substantially tangential to the leading portion of the baffle.
An apparatus constructed in accordance with the principles of the present invention can be made much smaller, and therefor less costly, than conventional dewatering apparatuses. Moreover, the apparatus is less damaging to the solid items separated from the liquid stream and, in applications involving potato processing, can be used to feed dewatered potatoes directly into downstream processing devices, such as peelers and slicers.
Other objects, features, and characteristics of the present invention, including the methods of operation and the function and interrelation of the elements of structure, will become more apparent upon consideration of the following description and the appended claims, with reference to the accompanying drawings, all of which form a part of this disclosure, wherein like reference numerals designate corresponding parts in the various figures.